Background: Allergic diseases like such as atopic dermatitis, asthma, and rhinitis have recently increased both domestically and globally. The present study was undertaken to select candidates with anti-allergic activity from plant resources. Methods and Results: Fifty-six plant extracts at 20㎍/㎖ were screened against β-hexosaminidase production and interleukin (IL)- 4 release in degranulated rat basophilic leukemia (RBL)-2H3 cells. The anti-allergy activity of three plant extracts selected from the preliminary screening experiment, Polygonatum sibiricum F. Delaroche (root), Pyrus pytifolia var. culta (Makino) Nakai (leaf), and Rehmannia glutinosa (Gaertn.) Libosch. ex Steud (root) were measured at concentrations of 2 - 250㎍/㎖ in three cell lines as RBL- 2H3, HaCaT and Jurkcat T cells. The assay showed the root extract of R. glutinosa to have an inhibitory activity of 4.2% - 28.6% on β-hexosaminidase production from IgE-sensitized RBL-2H3 cells. Each extract of P. sibiricum and R. glutinosa reduced IL-4 release in IgE-sensitized RBL-2H3 cells, respectively. The leaf extract of P. pyrifolia var. culta showed a significantly potent suppressive effect of 10.2% - 74.7% on the mRNA expression of tumor necrosis factor (TNF)-α in HaCaT cells sensitized with TNF-a and INF-g, and showed inhibitory effect of –8.6% - 90.9% on the mRNA expression of IL-2 in Jurkat T cells sensitized with PMA and A23187. Conclusions: The results showed that the root of R. glutinosa and leaf of P. pyrifolia var. culta could be useful candidates as antiallergy materials.

We evaluated the anti-allergic effect of black colored rice (Oryza sativa L.) and its main constituents, cyanidin 3 glucoside (C3G) and cyanidin (Cy) on scratching behavior in mice. The black rice extract (BRE) and its constituts inhibited the scratching behavior induced by compound 48/80 and histamin. To understand the role of intestinal microflora in the anti-allergic effect of C3G, which was suspected to play a key role in depressing scratching behavior, C3G was incubated with human fecal bacteria. Protocatechuic acid (PCA) was found within the 30 min and its concetration sharply increased. Vanillic acid (VA) was also detected in the incubated sample mixture. The anti-allergic effect of these compounds, C3G, Cy, PCA and VA, were investigated. PCA and Cy potentely reduced scratching behavior in mice induced by compound 48/80 and histamin. These findings enable us to conclude that intestinal bacterial metabolites, PCA and VA, produced by intestinal micro flora contributed to suppressing the scratching behavior induced by compound 48/80 and histamin.

The anti-allergic effect of C3GHi rice breeded from the cross of ‘Heugjinjubyeo’ and ‘Suwon 415’ was investigated. Antiscratching behavioral effects of the water extract of C3GHi was higher than Heugjinjubyeo. Orally administered BCRs’ extracts exhibited potent inhibitory activity against scratching behaviors which were induced by compound 48/80. The inhibitory effect of C3GHi against the passive cutaneous reaction was more potent than that of Heugjinjubyeo. These finding suggest that black colored rice, especially C3GHi, may inhibit scratching behaviors and passive cutaneous reaction, and its anti-allergic activities were increased by means of selecting high C3G rice seeds.